Re: [PATCH v4 07/16] x86/virt/tdx: Add tdx_alloc/free_page() helpers

[Dave Hansen]

On 12/3/25 10:15, Edgecombe, Rick P wrote:
> On Wed, 2025-12-03 at 07:41 -0800, Dave Hansen wrote:
>> It's fixed at a "page pair" in the ABI documentation, no?
>>
>> If Intel wants anything else, it should have documented that as the ABI.
>> So, as far as the code goes, it's a "page pair" now and forever. Linux
>> does not need to go out of its way to make it inflexible, but there's no
>> need to add complexity now for some future that may never come.
>>
>> I agree with Nikolay: KISS.
> Thanks Dave. Yes, let's stick to the spec. I'm going to try to pull the loops
> out too because we can get rid of the union array thing too.

Also, I honestly don't see the problem with just allocating an order-1
page for this. Yeah, the TDX modules doesn't need physically contiguous
pages, but it's easier for _us_ to lug them around if they are
physically contiguous.

Plus, if you permanently allocate 2 order-0 pages, you are _probably_
going to permanently destroy 2 potential future 2MB pages. The order-1
allocation will only destroy 1.